• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.3
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• pp.341-357
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• 2010

Forward Error Correction (FEC) techniques have been adopted to overcome packet losses and to improve the quality of video delivery. The efficiency of the FEC has been significantly compromised, however, due to the characteristics of the wireless channel such as burst packet loss, channel fluctuation and lack of Quality of Service (QoS) support. We propose herein an Adaptive Cross-layer FEC mechanism (ACFEC) to enhance the quality of video streaming over 802.11 WLANs. Under the conventional approaches, FEC functions are implemented on the application layer, and required feedback information to calculate redundancy rates. Our proposed ACFEC mechanism, however, leverages the functionalities of different network layers. The Automatic Repeat reQuest (ARQ) function on the Media Access Control (MAC) layer can detect packet losses. Through cooperation with the User Datagram Protocol (UDP), the redundancy rates are adaptively controlled based on the packet loss information. The experiment results demonstrate that the ACFEC mechanism is able to adaptively adjust and control the redundancy rates and, thereby, to overcome both of temporary and persistent channel fluctuations. Consequently, the proposed mechanism, under various network conditions, performs better in recovery than the conventional methods, while generating a much less volume of redundant traffic.

• The Journal of Korean Medicine
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• v.38 no.4
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• pp.110-117
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• 2017

Objectives: This study aims to evaluate the clinical effectiveness of a Korean medicine treatment on a traumatic spinal cord injury. Metohds : A 44-year-old male patient who had suffered a traumatic spinal cord injury was treated for two months. The effectiveness of complex Korean medicine treatments was measured using the Numeric Rating Scale (NRS) and the Manual Muscle Test (MMT). Result : We found that the NRS of pain caused by numbness was decreased from 7 to 0-1, and the overall motor measured by the MMT was also improved. The patient's walking state was changed from wheelchair ambulation to walker ambulation. Conclusion : Based on this finding, complex Korean medicine treatments may be effective in treating patients' pain, controlling paresthesia, and aiding the recovery function of activities in daily living. However, because of the limitation of our study, further high-quality research should be conducted.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.1 no.1
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• pp.10-13
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• 2008

Purpose: To evaluate the efficiency of needling and injection technique without steroid for symptomatic calcific tendinitis of the shoulder. Material and Methods: We chose 12 symptomatic calcific tendinitis patients, whose ages ranged from 35 to 64. Procedure ware dry needling and injection of prolotherapic agent near the lesion. Results: All the case revealed prominent improvement without limitation of shoulder function, especially in active painful stage. Conclusion: Sonographic injection technique for calcific tendinitis would be one of the good modality not only for symptomatic relieve but also good functional recovery.

• Korean Journal of Environmental Agriculture
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• v.33 no.3
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• pp.189-193
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• 2014

BACKGROUND: The aim of this study is to investigate the effects of Lycium chinense Miller fruit and its representative constituent betaine on reduction of immobility time and blood parameters in balb/c mice. METHODS AND RESULTS: We investigated the immobility time and the changes in aspects of blood biochemical parameters by the administration of L. chinense Miller fruit and its representative constituent betaine, after the forced swimming test. The immobility time was significantly reduced about 41.3% and 53.6%, respectively, in the animal of L. chinense Miller fruit and its representative constituent betaine-administrated group for 7 days, in comparison with that of the control group. The level of blood urea nitrogen was significantly decreased in L. chinense Miller fruit and its representative constituent betaine-treated group compared with the control group (P < 0.05), respectively. In addition, the interlukin-2 levels of mice in L. chinense Miller fruit and betaine treated group was increased compared with the control group. CONCLUSION: These results indicate that L. chinense Miller fruit and betaine might be helpful in the immune function improvement, enhance physical stamina, and fatigue recovery.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.4
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• pp.67-75
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• 2006

This study compared with the object of designation and the management practices for Protection Forests between Korea and Japan to establish the management and development directions of Korea's Protection Forest. 1. Water conservation forest from total areas of Protection Forests occupied 90.6 % in Korea and 68.4 % in Japan, respectively. The water conservation forest was the most important function among the Protection Forest's functions in both countries. 2. The 10 million ha of Protection Forest in Japan increased for last 100 years. The 100 thousand ha per year was designated as Protection Forest. In contrast, The 655,535 ha of Protection Forest in Korea decreased for last 42 years with decreasing of 15,000 ha per year. 3. In Japan, Protection Forest can be managed by forest silvicultural practices such as forest harvest, thinning, and pruning to recover and improve the Protection Forest's functions. 4. In case of Korea, it is necessary to a mid- or long-term counter plan to increase the area of Protection Forest by the government, and needs to the recovery and improvement of Protection Forest's functions.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.142-145
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• 2001

I did research or design technology of(integration) network of PSTN and PSDN in this paper. Network structure model in association with soft switching and access gateway can create various services based on web and live time and service fee at the rate of bandwidth which can't be provided by existing network based on SONET. Also, interns of capability(function) of each area and construction of local network subscribers, it has great recovery capability by separating each network as local areas. It indicates that it can additionally maximize the application of its own communication network and drastic reduction of communication cost because it is alternated to exclusive usage cost.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.16.1-16.1
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• 2011

Gas sensor properties of $WO_3$ nanowire structures have been studied. The sensing layer was prepared by deposition of tungsten metal on porous single wall carbon nanotubes followed by thermal oxidation. The morphology and crystalline quality of $WO_3$ material was investigated by SEM, TEM, XRD and Raman analysis. A highly porous $WO_3$ nanowire structure with a mean diameter of 82 nm was obtained. Response to CO, $NH_3$ and $H_2$ gases diluted in air were investigated in the temperature range of $100{\sim}340^{\circ}C$ The sensor exhibited low response to CO gas and quite high response to $NH_3$ and $H_2$ gases. The highest sensitivity was observed at $250^{\circ}C$ for $NH_3$ and $300^{\circ}C$ for $H_2$. The effect of the diameters of $WO_3$ nanowires on the sensor performance was also studied. The $WO_3$ nanowires sensor with diameter of 40 nm showed quite high sensitivity, fast response and recovery times to $H_2$ diluted in dry air. The sensitivity as a function of detecting gas concentrations and gas sensing mechanism was discussed. The effect of dilution carrier gases, dry air and nitrogen, was examined.

• Clinical and Experimental Pediatrics
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• v.56 no.1
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• pp.8-12
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• 2013

Asthma is associated with increased levels of eosinophils in tissues, body fluids, and bone marrow. Elevated levels of eosinophil-derived neurotoxin (EDN) and eosinophil cationic protein (ECP) have been noted in asthma patients. Higher levels of EDN and ECP are also associated with exacerbated asthmatic conditions. Thus, EDN, along with ECP, may aid the diagnosis and monitoring of asthma. Several groups have suggested that EDN is more useful than ECP in evaluating disease severity. This may partially be because of the recoverability of EDN (not sticky, 100% recovery rate), as ECP is a sticky and more highly charged protein. In terms of clinical utility, EDN level is a more accurate biomarker than ECP when analyzing the underlying pathophysiology of asthma. As a monitoring tool, EDN has shown good results in children with asthma as well as other allergic diseases. In children too young to fully participate in lung function tests, EDN levels may be useful as an alter native measurement of eosinophilic inflammation. EDN can also be used in adult patients and in multiple specimen types (e.g., serum, sputum, bronchoalveolar lavage fluid, and nasal lavage fluid). These results are repeatable and reproducible. In conclusion, EDN may be a novel biomarker for the diagnosis, treatment, and monitoring of asthma/allergic disease.

• Journal of Korea Foundry Society
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• v.33 no.1
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• pp.1-7
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• 2013

The effect of the Mo addition on the high temperature creep properties of the 9Cr-3W steel was also evaluated. Two experimental steels, (9Cr-3W and 9Cr-3W-0.5Mo), were prepared using a vacuum induction melting process, followed by hot rolling and heat treatment processes. Three types of precipitates, ($M_{23}C_6$, Nb-rich MX and V-rich MX) were observed in a typical tempered martensitic matrix. Significant effects of the Mo addition on the tensile properties were not observed. However, the creep properties at $650^{\circ}C$ under applied stresses of 140 and 150 MPa were considerably enhanced by the Mo addition. The microstructural observation after the creep test indicated that the addition of Mo could function to retain the recovery of the martensitic matrix, thus resulting in the enhanced creep properties of the 9Cr-3W-0.5Mo steel. Furthermore coarsening of the $M_{23}C_6$ carbides and formation of Laves phases were observed in both samples after the creep tests.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.4
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• pp.685-694
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• 2001

In this study, a transfemoral prosthesis system of which both stance phase and swing phase are controllable has been developed for the recovery of the biomechanical function of the amputated leg. It consists of a 5 bar link mechanism, a hydraulic-rubber knee damper for stance phase control and a pneumatic cylinder controlled via a microprocessor for stance phase control. The mechanical characteristics of the knee damper which absorbs the impact energy generated at the heel contact were investigated. The characteristics of the pneumatic cylinder essential for the speed adaptation of the prosthesis during swing phase were also studied for its mechanical characteristics. The prosthesis was subject to the clinical tests, and the gait characteristics obtained were very close to those of normal subjects. The stance and swing controlled prosthesis that were developed in this study showed good stability during the stance phase and showed good controllability during the swing phase.